A UC Berkeley-led study found that generations after it ended, descendants of those who suffered through the Great Chinese Famine of the 1950s and 1960s are still disproportionately vulnerable to infectious disease.
The study stemmed from an accidental observation while the research group was analyzing tuberculosis data provided by the Centers for Disease Control and Prevention in Sichuan, China, intending to chart the seasonal variation of tuberculosis by age group. The study’s lead author, campus postdoctoral student Qu Cheng, noticed that the cohort born during the famine contracted tuberculosis at a higher rate than projected. Further analysis showed that the offspring of those directly affected also experienced infection rates that were higher than expected.
“From Yemen to the DRC and Venezuela, famine is widespread and likely to become worse as the COVID19 pandemic continues to strain the global economy and supply chains,” said Christopher Hoover, study co-author and campus doctoral candidate, in an email. “Our research shows that these events echo through multiple generations, so we’ll be dealing with the consequences in terms of reduced human health for decades to come.”
According to Philip Collender, study co-author and campus researcher, the precise origin of the generational effect, however, remains unclear.
Collender said it may stem, in part, from epigenetics — a change in gene expression due to circumstances during a person’s lifetime that is then passed on to their descendants — or from social factors, such as higher poverty rates in famine descendants leading to an increased likelihood of contracting infectious diseases.
To rule out the possibility of direct transmission, in which parents with an increased likelihood of contracting tuberculosis would infect the children they live with, the researchers conducted a secondary analysis of sexually transmitted and bloodborne diseases such as HIV, which cannot be transmitted directly, and found a similar pattern, Collender added.
According to Cheng, this is the first time research has been done on the long-term, intergenerational ramifications of famine on infectious disease risk. While there have been other studies about the intergenerational health impacts of nutritional stress, Cheng said, previous studies focused on chronic health conditions such as Type 2 diabetes.
Collender called the research a promising “first step,” adding that more work needs to be done to understand the mechanism by which vulnerability remains elevated across generations, an understanding that could then be used to treat or suppress these effects.
For some of the researchers, the findings struck closer to home. Yue You, study co-author and campus doctoral student, said in an email that many of her family members experienced the Great Famine, which remains an “agonizing memory” 60 years later.
“My grandmother, who has gone through that famine, told me many stories of people eating tree barks and ‘Guanyin Soil’ in the hope of stopping starving, yet died from that with huge bellies because humans cannot digest the ‘Guanyin Soil,’” You said in the email. “The past is not only stories, it still has direct impacts today.”